The disused quarry in Derbyshire is known locally as the Blue Lagoon
Police say a body found by force divers was that of a 15-year-old boy who went missing while swimming in a disused quarry in Derbyshire.
The body of Ryan Walker, 15, from Holmegate, was found on Sunday night at Far Hill Quarry, near Ashover.
Emergency services were alerted shortly after 1500 BST by people who saw the 15-year-old calling out for help.
Derbyshire Fire and Rescue crews handed the search to the police underwater team on advice from a medical expert.
A Derbyshire Police spokesman said: "Search teams made up of police and fire crews were at the scene for a number of hours.
"A specialist police diving unit from Nottinghamshire, which had been called in to assist, recovered the boy's body from the water at 2050 BST."
Insp Ian Palfreyman from Derbyshire Police warned against playing in lakes and quarries.
"What people don't realise are the real dangers there are. The water is always a lot colder than people expect and this can often send people into physical shock.
"Also often people cannot see any possible obstructions beneath the water which they may get caught or trapped by.
"The simple message is to stay out of open water and specifically quarries in general. They are dangerous places which should be avoided."
Fire crews from Matlock, Clay Cross and Chesterfield attended the incident at the quarry, which is known locally as the Blue Lagoon, along with a police boat.
A post-mortem examination is set to take place to establish the cause of death. The coroner has been informed and an investigation is under way.